well if your looking for a good roller, look at the torque boxes, strut towers, the front floor pans rust alot of times, bottoms of doors, where the antenna is on the passenger fender, and they all rust around the reay key cylinder in the trunk, alot of mustangs ive seen to have front lower core support damage from running into a curb or something so i always check that as well
I used to always check craigslist in southern states, they go for cheap and usually are clean plus most drives are only 8 hours